1. Field of the Invention
The present invention relates generally to current sources, and more specifically to providing such current source in environments such as analog to digital converters (ADC) and digital to analog converters (DAC), which may require the current source to be switched on and off at high frequencies.
2. Related Art
A current source refers to a component which provides a substantially constant current independent of the load offered to it. There are several situations in which it is desirable to switch on and off providing such constant current. For example, in high speed DACs, current sources may be used to control the strength of the output signal and the current may need to be accordingly switched on and off at a correspondingly high frequency. Such current sources operable to be switched at high frequency are termed as wideband switched current sources.
One general requirement in such situations is that the magnitude of current be maintained at the same level even when switched at high frequencies. For example, in the context of DACs, such a feature enables a DAC to provide a linear response (i.e., the magnitude of current output is linearly proportionate to the input digital value provided to the DAC).